Brand new issue in my 2016 sierra Z71.
After I am stopped at a red light, the tachometer will rev up to near red with the slightest tap of the accelerator with no movement. Shifting into neutral will have the RPM behaving and sounding normal. I will not have any forward gears or reverse. Turning the truck of, and restarting will have the truck back to normal for a time (as long as I don’t stop at any red lights).